// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_PUBLIC_RENDERER_MEDIA_STREAM_AUDIO_RENDERER_H_
#define CONTENT_PUBLIC_RENDERER_MEDIA_STREAM_AUDIO_RENDERER_H_

#include <string>

#include "base/callback.h"
#include "base/memory/ref_counted.h"
#include "base/time/time.h"
#include "media/base/output_device_info.h"
#include "url/origin.h"

namespace content {

class MediaStreamAudioRenderer
    : public base::RefCountedThreadSafe<MediaStreamAudioRenderer> {
public:
    // Starts rendering audio.
    virtual void Start() = 0;

    // Stops rendering audio.
    virtual void Stop() = 0;

    // Resumes rendering audio after being paused.
    virtual void Play() = 0;

    // Temporarily suspends rendering audio. The audio stream might still be
    // active but new audio data is not provided to the consumer.
    virtual void Pause() = 0;

    // Sets the output volume.
    virtual void SetVolume(float volume) = 0;

    // Returns current output device information. If the information is not
    // available yet, this method may block until it becomes available.
    // If the renderer is not associated with any output device, |device_status|
    // of OutputDeviceInfo should be set to OUTPUT_DEVICE_STATUS_ERROR_INTERNAL.
    // Must never be called on the IO thread.
    virtual media::OutputDeviceInfo GetOutputDeviceInfo() = 0;

    // Attempts to switch the audio output device.
    // Once the attempt is finished, |callback| is invoked with the result of the
    // operation passed as a parameter. The result is a value from the
    // media::OutputDeviceStatus enum.
    // There is no guarantee about the thread where |callback| will be invoked.
    // TODO(olka): make sure callback is always called on the client thread,
    // update clients accordingly and fix the comment.
    virtual void SwitchOutputDevice(
        const std::string& device_id,
        const url::Origin& security_origin,
        const media::OutputDeviceStatusCB& callback)
        = 0;

    // Time stamp that reflects the current render time. Should not be updated
    // when paused.
    virtual base::TimeDelta GetCurrentRenderTime() const = 0;

    // Returns true if the implementation is a local renderer and false
    // otherwise.
    virtual bool IsLocalRenderer() const = 0;

protected:
    friend class base::RefCountedThreadSafe<MediaStreamAudioRenderer>;

    virtual ~MediaStreamAudioRenderer() { }
};

} // namespace content

#endif // CONTENT_PUBLIC_RENDERER_MEDIA_STREAM_AUDIO_RENDERER_H_
